Commit dc82b1a5 authored by Diogo Jahchan Koike's avatar Diogo Jahchan Koike Committed by Long Li
Browse files

ntfs3: Change to non-blocking allocation in ntfs_d_hash 

mainline inclusion
from mainline-v6.10-rc2
commit 589996bf8c459deb5bbc9747d8f1c51658608103
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRDE
CVE: CVE-2024-50065

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=589996bf8c459deb5bbc9747d8f1c51658608103



--------------------------------

d_hash is done while under "rcu-walk" and should not sleep.
__get_name() allocates using GFP_KERNEL, having the possibility
to sleep when under memory pressure. Change the allocation to
GFP_NOWAIT.

Reported-by: default avatar <syzbot+7f71f79bbfb4427b00e1@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=7f71f79bbfb4427b00e1


Fixes: d392e85fd1e8 ("fs/ntfs3: Fix the format of the "nocase" mount option")
Signed-off-by: default avatarDiogo Jahchan Koike <djahchankoike@gmail.com>
Signed-off-by: default avatarKonstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: default avatarLong Li <leo.lilong@huawei.com>
parent 9d0af12b

fs/ntfs3/namei.c

+2 −2
Original line number Diff line number Diff line
@@ -501,7 +501,7 @@ static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name) 
	/*

	 * Try slow way with current upcase table

	 */

	uni = __getname();

	uni = kmem_cache_alloc(names_cachep, GFP_NOWAIT);

	if (!uni)

		return -ENOMEM;
@@ -523,7 +523,7 @@ static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name) 
	err = 0;



out:

	__putname(uni);

	kmem_cache_free(names_cachep, uni);

	return err;

}